/*
 * Copyright 2010 Red Hat, Inc. and/or its affiliates.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.drools.core.util;

import java.math.BigDecimal;
import java.math.BigInteger;

/**
 * 这个是我重写的源码，用来测试double数值转换
 * Utility methods for math classes
 */
public class MathUtils {

    public static BigDecimal getBigDecimal(Object value) {
        BigDecimal ret = null;
        if (value != null) {
            if (value instanceof BigDecimal) {
                ret = (BigDecimal) value;
            } else if (value instanceof String) {
                ret = new BigDecimal((String) value);
            } else if (value instanceof BigInteger) {
                ret = new BigDecimal((BigInteger) value);
            } else if (value instanceof Double) {
                ret = BigDecimal.valueOf((Double) value);
            } else if (value instanceof Number) {
                ret = new BigDecimal(((Number) value).doubleValue());
            } else {
                throw new ClassCastException("Not possible to coerce [" + value + "] from class " + value.getClass() + " into a BigDecimal.");
            }
        }
        return ret;
    }

    public static BigInteger getBigInteger(Object value) {
        BigInteger ret = null;
        if (value != null) {
            if (value instanceof BigInteger) {
                ret = (BigInteger) value;
            } else if (value instanceof String) {
                ret = new BigInteger((String) value);
            } else if (value instanceof BigDecimal) {
                ret = ((BigDecimal) value).toBigInteger();
            } else if (value instanceof Number) {
                ret = BigInteger.valueOf(((Number) value).longValue());
            } else {
                throw new ClassCastException("Not possible to coerce [" + value + "] from class " + value.getClass() + " into a BigInteger.");
            }
        }
        return ret;
    }
}
